Electrical circuits and controls for sequential operation of a plurality of loads



1955 B. F. HOLMES ET AL 2,700,737

ELECTRICAL CIRCUITS AND CONTROLS FOR SEQUENTIAL OPERATION OF A PLURALITY OF LOADS Original Filed Dec. 10, 1947 5 Sheets-Sheet l lOO INVENTOR m Burfun F. Holmes Herben H. Heme Pl a w b M 1955 B. F. HOLMES ET AL 2,700,737

ELECTRICAL CIRCUITS AND CONTROLS FOR SEQUENTIAL OPERATION OF A PLURALITY OF LOADS Original Filed Dec. 10, 1947 5 Sheets-Sheet 2 nwu mo 01:5...

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1955 B. F. HOLMES ET AL 2,700, 37

ELECTRICAL CIRCUITS AND CONTROLS FOR SEQUENTIAL OPERATION OF A. PLURALITY OF LOADS Original Filed Dec. 10, 1947 5 Sheets-Sheet 3 EJIEUUED Jvwonfov Burfan E Ha/ mes fi Hererf H. HE/I76/8/ m am/3% fatty/wa ET AL 2,700,737 3143 FOR SEQUENTIAL OF LOADS 1555 B. F. HOLMES ELECTRICAL CIRCUITS AND CONlR OPERATION OF A PLURALITY 10, 1947 5 Sheets-Sheet 4 OrigiLal Filed Dec.

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ELECTRICAL CIRCUITS AND CONTROLS FOR SEQUENTIAL OPERATION OF A PLURALITY OF LOADS Original Filed Dec. 10, 1947 5 Sheets-Sheet 5 United States Patent ELECTRICAL CIRCUITS AND CONTROLS FOR SEQUENTIAL OPERATION OF A PLU- RALITY OF LOADS Burton F. Holmes and Herbert H. Heindel, Toledo, Ohio, assignors to Schultz Die Casting Company, Toledo, Ohio, a corporation of Ohio Original application December 10, 1947, Serial No. 790,838, now Patent No. 2,532,256, dated November 28, 1950. Divided and this application June 30, 1953, Serial No. 365,101

18 Claims. (Cl. 307-112) The main object of this invention is to provide electrical circuits and controls for sequential operation of a plurality of loads for a single cycle under manual conltrol, said single action stopping at the end of one cyc e.

To this end, suitable circuits with relays and controls extend from a source of current supply controlled by a manual switch with a one cycle tying-in relay to energize the first load; then a plural acting timing mechanism is set into operation by a machine-operated part, to sequentially energize several loads in timed relation; means are provided then to automatically reset the timing mechanism and finally deenergize the first load and bring the action to a stop after one cycle with all controls, relays and circuits in the original condition ready for recvcling.

Moreover, it is the object of this invention to provide several interlocking safety controls, to require, for example, that the first load be energized before the second may operate, and also that each subsequent load be energized in turn before a sequential load is actuated.

It is also an ob ect of this invention to provide resetting of the timing of certain loads which must occur before release of energization of the last load and return cl all circuits to normal position.

Another safety feature of the present invention is a special requirement of the machine-operated part which cycles the machine in that, unless this particular switch has been properly seated and the operator pushes the cycling control button, no action would result since the tying-in relay would not be energized if said machineoperated switch had not previously been properly seated.

A further safety control in the associated circuits, relays and timers is herein provided in that if the machineoperated switch of the cycling system were accidentally closed, the remainder of the normally cycling steps (which might, under such conditions, be dangerous) could not result, since we provide by our invention a system requiring closing of certain switches by the previous steps of the cycle before subsequent steps may occur, even if certain parts were accidentally or even deliberately operated.

A further object of this invention is to provide a shift-over switching and controlling arrangement in electrical circuits and controls operating at one time an automatic network for sequential operation of the plurality of loads in a single cycle and at another time a manual control to permit set up, repair and adjustment of the machine to which the electrical controls are applied. To this end, the new works include certain common leads and controls, one for manual manipulation and the other for automatic action extending thereto from a source of current supply. The manual network however actuates only one of said plurality of loads while the others remain inactivethus providing a safety factor for workmen when setting up new work in a given machine where this electrical system is used or for adjusting or repairing the same.

Further objects and advantages are within the scope of this invention, such as relate to the arrangement, operation and function of the related elements of the structure, to various details of construction and to combination of parts, elements per se, and to economies of manufacture and numerous other features, as will be apparent from a consideration of the specification and drawing of a form of the invention, which may be preferred, in which:

Figure I is a diagram of the entire electrical circuits and controls of one embodiment of our invention;

Figure II is a partial diagram of the power inlet circuits;

Figure III is a diagram of the energizing circuits for the first load showing the manual control;

Figure IV is a diagram of the control circuits with the timer mechanism for energizing the next load; and

Figure V is a similar diagram for energizing (through the timer) another load.

Figure I hereof is identical with Figure VIII of our prior case, original application, Serial No. 790,838, filed December 10, 1947 (Patent No. 2,532,256), and of certain other divisions thereof, including application Serial No. 196,914, filed November 21, 1950, and application Serial No. 335,876, filed February 9, 1953, the electronic timer mechanism shown including the space discharge tubes 1, 2, 3 and 4, this case being a division of our prior cases.

This present invention concerns primarily the control for loads 6, 7 and 8, which in the original case and in the divisional cases referred to are illustrated for the purpose of operating a die casting machine, mainly through solenoids 9, 10 and 11. An oil pump for producing an operating fiuid under pressure is also indicated as actuated by electric motor 12. A common unitary switch 13 having switch blades 14, 15 and 16 for supplying current to said solenoids 9, 10 and 11 is connected by leads 17, 18 and 19 to the supply lines 20, 21 and 22.

As in our previous cases, the 400 volt A. C. supply is through said input lines 20, 21 and 22. The outside power to the system is through the contactor switch mechanism 23 and, in particular, supply lines 21 and 22 have lead 24 (see Figure II) for connection to the main transformer 25 from the secondary of which leads connect to another transformer 26. This transformer 26 has a 24 volt secondary 27 for supplying 24 volts to the main controlling system forming the basis of this present case.

As more clearly shown in Figures II and III, we provide two interconnected relays 28 and 29 for receiving energy from said transformer 26 to set up the control system. These relays 28 and 29 are initially energized when the system is connected up and set for automatic action by the various connections including switch shown at 23. For example, when switch 23 is closed, relay 28 is energized and certain circuits necessary to the entire system as shown in Figure I will be established and relay 28 must be so energized to effect proper operation of the 24 volt control system which forms the basis of this particular division. Moreover, upon energizing relay 28 through certain circuits and controls shown in Figure I, the other relay 29 will be energized. When these two relays 28 and 29 are energized, the 24 volt control circuit for loads 6, 7 and 8 may be established.

To this end, we provide (see Figure III) a series of connections from transformer 26 to the cycling manually momentarily operated push button 30 by a lead 31 to a point 32 of relay 29, then by lead 33 to lead 34 to lead 35, through lead 35 to lead 36, hence, through the coil of tying-in relay 37 to lead 38 to the first or normally closed position of the two-position machine part operated microswitch 40. A lead 41 connects microswitch 40 to said switch button 30. The other side of said manually controlled 24 volt control circuit includes part of lead 42 connected to manual switch 30, switch 43 and lead 44, lead 45 to lead 46 and from lead 46 through lead 47, lead 48 to closed point 49 of relay 29 and by lead 50 and lead 51 to the other side of the secondary winding of transformer 26.

A shunt circuit for by-passing said push button 30 is connected from said lead 38 at junction 52 above said coil 37, said junction 52 connected through lead 53 and closed point 54 of special relay 55, lead 56, closed point 57 which has been closed by coil 37, lead 60, point 61, hence, by lead 62 to lead 42, bypassing push button 30. The special relay 55 acts at the end of the cycle to open the dies and aids in effecting return to initial position of the circuits just describe 'As alsoshown.imFigurelII, the connections of the 24 volt control circuit for operating the first of said plu- 'rality of loads; coil 6 includes a lead 64 from tying-in relay 37 then through closed point 65 on said relay 37, lead 66, then point 67 on .automatic control relay28 "through lead 68 to coil 6 and from co'il56 back ,onlead "69"through closed point 70 on said automatic control relay 28 to lead 71 and from lead 71 to live wire-connection'48'and, hence, 'to transformer 26 through the connections above described. It will'be seenthat ,Ithis first 'load'control circuit 'by-passes the first position ..of microswitch 40.

As' separately shown in FigureIV, the circuit for energizing the second load 7 of said pluralityof loads in- "cludes a connection at 74 from the live lead35'energizedifrom transformer 26, said connection'74 having 'lead 75extending'through'the second position-76.0f said microswitch. From hence a lead'77 connects thecoil of "a key relay 78, to lead 46 and live lead 47 for energizing "said 'key'relay 78. Said second loadenergizing circuit al'so-"includes connections from live lead .36 adjacent jtying-in'coil37 through closed point 79 of said key, re-

lay" 78," hence, by'lead' 80,'lead 81 to. coil'7, hence, by flea'd"82 to the first stage of a. timing device andfrom 'sa'idfi'rst stage to live lead'48, hence, returning to trans former 26.

Referring to Figure V, we show the 24 volt control "circuit for the third load or coil 8. Here, it will be seen that the previous circuits having been energized, we :havean extension 83 from the live lead 80 to the coil 8 and from said coil 8 through a lead 84 to the second stage of the timing device and from said second stage by flead 85 to live lead '48.

'As brought out in our revious cases and indicated abovejthe timing vmechanism includes means to reset "the'first and second timers, specifically, tubes 1 and 2, and alsomeans operated by a fourth stage, tube 4 to open .ijthejswitch point 53 of special relay 55. This, in turn, .also deenergizes tying-in coil 37 andopens point .65 and,

Thence,deenergizesthelfirst or die closingload; 6. Con-' sequently,.all circuits are eventually restored to initial position. ready to be recycled by an operation. of the push button control 30.

Power input-circuit, of Figure I -.In. ordertomore completely showthe, interaction of .lthevvarious load 'circuitslhereof, we include herein av description of the main circuits of the entire system as ilhistr'ated in Figure I hereof.

" The three-phase inlet leads 20, 21 and 22 are. for a- .A safetyfeature ishere provided,-in that if contactor 23 for any reason opens, it removes thepowerirom the .main injection operating air valve-so leno1ds 10 and 11 sand-oil valvesolenoid' 9, :thus prevent ng squirt ng metal -finto the room. r-Tube supply circuits, transformer connections, 'elc.

'Figure I IWe-als'o provide a 110 .volt circuit from main trans- :Qformer ZS tosupnly another transformer 88 for supplying energy for lighting the filaments of tubes 1, 2, 3 and' .4 at 6.3 .volts,-another circuit'for the heating element there f as well. as the bias circuits hereafter described. weialsoinclude a volt heating elementfor a rectifier -tubc89 and a high voltage for the plates of the same. This rectifier tube 89 supplies D. C. current to the grid bias or control circuits for controlling the firingofthe ..:main..thyratron tubes 1, 2, 3 and 4.

QThellO Volt circuit from .maintransformer includes ".fuse90..lead.91-.to normallyv open point 92...lead- 93.10

. connecting point 94. which supnliesthroughlead 95,. ,the-= TTIOvolt primary of transformers88. .The lltlvolt circuit from main transformer -25also,has lead96 connected to.lead 91.'from said transformer, said-lead 96 ext.end,ing

1.4 terminal-9110 s pp y o voltsatots assu p r nd h at,

control.

with contactor 23v Austandard Lead ,1 rcm poi \113 9n ec .-With lea' and a ,the plate circuit.of ,tub 1, we have a Referring now to the above-mentioned 220 volt circuit from transformer 25, the same includes fuse 9 8, lead 99 to primary of transformer 26. The other side 'of the primary of said transformer 26 is grounded at 100 from lead 101.

This transformer 26 has ,a 24 volt secondary winding 27 with lead 51 whieh,'by lead*102, passes through coil 28, the other side-of coil 28 having lead 103 connected to switch .104 (normally open). The return-circuit includes lead 105, and lead 31 to the other side of the 24 volt transformer 26. Thus, when switch 104 in this circuit is closed, coili28 isenergizedand this closes switchesto effect an application, of .voltage to. the system forautomatic operation of the machine. Therefore, switchl-(M is a key switchbymeans of which the mechanism may be disconnected-from all automatic operation and, in certain instances, the machine may be operated manually.

This 24 volt control circuit also connects through lead 51, lead 50, to both points 32 and -49-ofrelay 29.

Relay 29 is locatedin an-arrangement of circuits provided to give a delaying action to the application of the 220 volts to theplates of the mainnetwork thyrat-ron tubes 1, 2,3 and4 toallow said .tubes .towarmup. This 220 tp at r u i ,al osqnt ol e by t e mai b a for said tubes throughcqil 106as hereinafter set forth,

but the delayed warm up control action is accomplished by a mercury time ,delay, mechanism ,106, ,107 and the connections arecontrolled by ;relay,.29. Thus, this 24 volt circuit is connected from transformer ;27 -by lea d 51 to lead 108.1throughpoint107 of thefcombinedcholce coil and rclay 106 and back by lead 109.,to the coil of relay 29. The coil 29 is connectedon theotherside,by

i leadj31 to transformer 27.

Each of the plate circuits forthe tubes are connect- :ed. to, ground ;termi.nal 100 from the main transformer f 25, ;s1nce .each ,cathode circuit is grounded at 101,. as

shown. On the other side fromsaid transformer ;.25,

, the plate circuits .include the fu sc, 98,;lead- 110 .t o, normally openpoint 111 .onrelay 28, which point is closed in the automatic position of theapparatus. l-"rronr po int .111 we provide QleadllZ'tonorriiallyopenpoint 113- it relay 29, whichpoint is also closed inthe antomatic rna- ,chine position but only after the timedelay-for thetube warm up hastaken place-in yiewof switch 117, supra.

the tube plate circuits connect to.-wire-;-1 15. I

lead 117, connected from lead 115 to resistor 118 -to limit the current flow, 168111-1910 coil 1 20 and,lead 121-totheplate of tube; 1. The cathode circuit-of tube 1.;is -grounded as i dicated at 101 by a circuit 122 and hencecQmpletesthe ;ci rcu it .to themain-transforrner 25,;since the lattertis grounded .at--10 0,;as stated supra. -We;also-;have a .cpndenser;.;123 connected across coil 1.20.to,suppiy current ;to the relay ,coil on the .negative one-half cycle and; prevent chatr ng of t e. poi ts co t ol ed yxe y, 2

t T other tubes;2, 3 and 4 are similarlyconnected. Thus, for tube ;2, l e a d 124-. is connected tothe lead 115 Qmmo a o-a1l fa be 1.2.13 nd a rindica e tsuu L ead;; 124, connects thr ough;resistor;125,..lead 126,-- 10 -,-coil .127, hence, by ai;lead.;128,=to the plate,'of tube-2 as;;.sho wn. A; condenser 129 ;is ,con-nectedacross leads 126 and 128 for coil 127 as shown.

.FOI' .connectingtube 3, we-provide. aalea'd. 130 ,passing through; theresistor 131 to lead 132,-v which connects with coil 133. having lead '134connected-to the .plate; of tube 3. A l condenser 135 .is connected :across leads i'132n and-134.

Thecathode circuit of tube 3 is grounded as indicated-by circuit 136.

' For. tube 4,.wealso provide a lead 137 connected with a: common :connectinglead v1'15 limiting resistor 138, 1ead 1.139, coil 55,. lead141, to the .plate of .tube, 4. :zWe-xalso -..prov -ide aicondenser :142 across-.leads-139...and 141 as, in

the case. of the, other; three. tubes. ,4- is: also lgroundedby circuit 143,.asindicated.

The cathode; of. tube L F FCHiI tThezbiassupply for each ofltubeszl, .2, Sand -4.lwhich is from a common source to each tube, willnow-bedescribed.

l 10 voltsfrom' the; main transformer 25' through; relay has three secondaries, one 144 for filaments of tubes 1, 2, 3 and 4.

The transformer 88 the 6.3 volts for the (Tubes are thyratron.) I

Another secondary output circuit of 5 volts is indicated 145 for the rectifier tube 89.

The third secondary from transformer 88 constitutes a source for supplying the bias for the several thyratron tubes 1, 2, 3 and 4. The current for the bias is changed from alternating current to direct current and, to this end, we provide rectifier tube 89 connected by leads 146 and 147 joined on the outside terminals of winding 148 of transformer 88 and to the plates of rectifier tube 89 as shown. The cathode of rectifier tube 89 is grounded as shown at 94. Parallel to the plate cathode circuit of rectifier tube 89 is a condenser circuit 149 having a filter condenser 150 located therein. We also provide in the grid circuit for the main thyratron tubes a voltage regulator tube 151 grounded as shown so that the direct current from the rectifier tube 89 is supplied to the plate of regulator tube 151 as indicated. The outlet terminal of regulator tube 151 is connected by lead 152 to lead 153 and also to lead 154 which is the main bias supply lead for the thyratron tubes 1, 2, 3 and 4. We also provide a bleeding resistor 155 in a circuit parallel to the regulating tube 151 as shown, connected with the bias supply lead 154.

The relay and controlling coil 106 is connected by a lead 152 to the output lead 152 of the regulating tube 151, said coil 106 being also connected by lead 156 through resistor 157 to the center of winding 148 which places coil 106 (iin series with the grid circuit for the thyratron tubes Our connections for these tubes also forms a time delay for the warming up of tubes 1, 2, 3 and 4, since relay 106, when energized, closes points 107, there being a time delay on the make of said points 107 with a well-known type of switch which has a quick break.

Moreover, this relay 106 provides a safety arrangement, since failure of any part of the bias supply will cause 107 to open, dropping out relay 29 which disconnects the plate circuits of the tubes 1, 2, 3 and 4. This also drops out the 24 volt control circuit to the automatic operation.

Connections for the bais supply voltage and tubes 1, 2, 3 and 4 The above circuits and the tubes 89 and 151 provide means to produce the bias voltage for the main thyratron tubes 1, 2, 3 and 4. We will now describe its connection to these tubes. Thus, we have a main bias supply lead 154 joined to lead 153 as shown, which lead 154 connects with three points (normally closed) on relay 158, points 159, 160 and 161. Lead 154 is also connected with the points of relay 133, namely, points 162, 163, 164 and 165. This lead 154 also has a connection to lead 166 to a contact 167 of relay 120. Lead 154 is in the main bias supply line for all four tubes.

For tube 1, bias is normally supplied from lead 154 to point 159, lead 168, resistor 169, the lead 170, to the grid of tube 1.

For tube 2, the main bias is from point 160, lead 171, resistor 172, lead 173, to the grid of tube 2. This main bias lead 154 also has a connection for an auxiliary circuit for tube 2 by lead 166 to a contact 167 of relay 120 controlled by tube 1. For tube 3, the main bias includes lead 175 from point 161, to resistor 176, lead 177, to the grid of tube 3. Tube 3 also has an auxiliary bias circuit, since we provide a lead from bias line 154 to point 164 of the relay 133 as shown. We also provide a lead 164 from point 164 to point 178 of relay 127 of tube 2. Then, we also provide a lead 179 connecting with lead 175 to the grid of tube 3. Hence, the auxiliary bias for tube 3 is so connected as to have in series therewith a switch controlled by the relay for tube 2.

For tube 4, the bias includes a lead 180 from point 165 to resistor 181, lead 182 to the grid of tube 4. As the necessary part of the operation, as will hereinafter appear more fully, we also provide additional temporary bias circuits for tubes 1 and 2. This additional bias for tubes 1 and 2 includes a circuit from switch point 162 of relay 133 by way of lead 168 which connects to lead 168 to the bias of tube 1. For tube 2, this additional temporary circuit is connected with relay point 163 by which also charges condenser lead 171' which connects with lead Sequential firing of tubes We have provided means for causing tubes 1, 2, 3 and 4 to fire" in sequence one after the other, and, moreover, any subsequent tube in the series cannot fire until the preceding tube has fired. The circuits and means for accomplishing this will now be described. Thus, when relay coil 158 is energized, this opens points 159, and 161, removing the main bias from tubes 1, 2 and 3. However, bias for tube 2 is now being supplied through an auxiliary circuit including a connecting lead 166 extending from lead 154 to switch point 167, lead 183, lead 171, resistor 172, lead 173 to grid of tube 2. When tube 1 fires (at the end of its time delay, to be described), relay 120, through lead 121, is then energized and normally closed point 167 now opens, removing the auxiliary bias from tube 2.

Also, the firing of tube 1 and energizing of coil 120, closes the normally open point 184, thereby applying 24 volts to the power relay 7 by leads 82 to valve 10 to operate metal injection at reduced pressure, as will be pointed out.

Firing of tube 2 At the expiration of the time delay for tube 2, tube 2 fires (the auxiliary bias being removed by firing of tube 1, as stated supra). The bias now on tube 3 is by reason of the auxiliary bias circuit described above. Firing of tube 2 opens normally closed point 178 of relay 127 which removes this auxiliary bias from tube 3.

The energizing of coil 127 also closes normally open point 185 which, through lead 186, energizes relay 8 for operating the check valve mechanism 11 to give the full shot of metal used in the die casting machine.

Firing of tube 3 Removing bias from tube 3 allows tube 3 to fire at end of its time delay energizing the coil of relay 133, closing normally open points 162 and 163, thereby reapplying the third or temporary additional bias to tubes 1 and 2, thus resetting these tubes and their associated plate circuit relays.

Firing of tube 4 to open by a spring return of the die actuating control mechanism.

Time delay circuits for tubes 1, 2, 3 and 4 For each of tubes 1, 2, 3 and 4, we have a time delay network for the bias circuits thereof which includes lead 168 (bias supply lead for tube resistor 169), lead 170 to grid of tube 1. Before normally closed point 159 opens, there is a circuit through resistor 169, lead 170, 188 which, until the bias is removed, supplies a voltage to grid 1. However, when switch point 159 is opened, condenser 188 is discharged through adjustable potentiometer 189 (which may be variably set by the operator) and current limiting resistor 190 to ground 122 as shown. The other side of the bias circuit and tube cathode is grounded as described supra. Thus, the setting of the adjustment on potentiometer 189 determines the time for discharge of condenser 188 which, when it reaches critical grid voltage of tube 1, allows the tube to fire. Resistor 190 limits the current for a very low or offsetting of the potentiometer 189. Resistor 169 has two purposes, one to prevent main bias supply from being shorted in case con denser 188 fails. Also it provides a buffer action to prevent burning of point 159, due to sudden inrush of current to condenser 188. It will be understood that we have provided similar potentiometer time control discharge networks for each of the other tubes 2, 3 and 4 and in the drawings, we have used the same numerals as for tube 1.

ReGPRlyinggbias-Jar tubei3 1 The bias control of the tube 3 (and also 1 and 2) is interlocked with.theamicroswitch.40.v which switch, in turn, is actuated by the rack on the machine, which rack is operated by the hydraulic system for the i die v operating mechanism; "The -microswitch"also has point 49 (normall-y closed):

Glosing-of point 'byg said racleor" machine operatedpart actuates relay 78; This isaccomplished by circuits connected-with. power input --relay 29 which includes lead 48 fromcontact 49 of relay 29', andleads ;46 'and 47'; Another lead 46' 'als'oconnects from lead 46-toxa point 1-98 (normally-- open) of relay Gnthe other side 'of coil 78,- 'atlead-77"connectswith normally open sid'e 7 6 of microswitch 40, referredto supra; and lea'd 7 5; leads 35;.34 and 33-to normally open point -32=of relay=29 When;-coil '78 is energized, 'coil-of'relay' l'58-isralso energized. Relay-78has-three=normally open -points"79, H

191 and 192. The connection from relay78 to relay 158 includes point 192', lead- 193," relay 'coil- 158: From the other 'side of"relay-"158,-.lead 19'4' connects "to lead 56; point-' 57 of relay37; the other side'of thet'switch 57 has a lead extending to terminal 61, hence, bylead 62 to point 43 which also connects to lead 44 and by connection 45 to lead 77 completing the circuit for energizing coil-78 and,- hence, coil. 1'58; Energizingcoil 158E opens all three points 159, 160 and 161, which removes-bias from tube -1and allows it'tol-"be removed in sequence from tubes 2*and 3; and the-bias-totube 3--is'--reappliedby'point 161- of relay ISSWhen-Ielay 158 is-deenergized as' the machine opens bybreaking the-microswitch at" point "/6.

Riessu-reswitch control 6 for preventing, machine from openingpwhenmetal is being injected into dies We provide a spccialsafety control in connection with preventing metal injection when the dies are open and also an "improper action in'case "the operator accidentally presses control part:

Thus, 'fronr'relay 28 (to which currentis supplied 'from transformer 27); we provide 'a circuit from point 70 of relay 28*to a'pressure' switch 195- by'leads 71, 196, 47, 197, bulb 198, lead 199, 35, 36, point'191' ofrelay 78',- lead 200 to pressurei.switch.,195. This pressure switch 195 is located acrosstthe die open.v and closing control circuit in" such a way as to prevent'themachine opening, but cannotaccidentally'close it, Whenthem'achine is in automatic controlposition; relay'29is energized,

thereby closing points 49-and :points 32',asstated supra, and 24 voltsissupplied throughpoints'49', leads 48, 196, 71 to normally open point'7tl on' relay 28' and in the automatic position, thispoint 70ris closed, .allowingcurrent then present at point 70' topass :through"lead"69 to coil of relay 6*to'contro'l" coil-9-. The other side' of relay-"6 by-lead 68 -connects witha normally open point 67 (closed in automatic position), lead 66, to point of relay137. From relay 357. the-.other: side of: 65 connects by lead 36' to return control voltage lead 34, point 32 of relay-29"supplying-energy at 24'volts from transformer-2'6;

Point 191- on relay 78 is primarily for connecting pressure-;switch=195 which is an' electrical contact on a pneumatically 'operated'mechanical pressure switch in -suchamanner 'thatthe pressureswitch, while it may holdthe'machine'closed as longasair pressure exists on switch 195,- yetyif air pressure issupplied accidentally such-action will not result in the closing of machine from an' openposition-since'relay 78 must be energized to hold point 191closed' before the pressure-switch can be effectiveto' supply energy to the coil 6 (die closing). If switch point 191 is .open', such connection will :be broken. Theimicroswitch point. 76 controls relay 78, and the machine. must the closed before 78*is energized. Hence, ifJthe-machine is tnot closed, v78 isdeenerg-izedandpoint 191-,isop en.-s o thatno energy can be supplied to. coil '6;

Hence, wahaveprovided not :only a=..dnal .safetycom trol which; will. render& inoperative. the: metal injecting meansiifmot"zin-thekcorrect position of one'or the-other of itsltwo-position locations, since not only must-the microswitch be in correct position but-the pressureswi'tch 195 is connected inseries, and-therefore, simultaneously controls the act-ion of *the machine to prevent opening 8 ofrtherdies :if themetal injection controlling meanssis :in abnormal condition.v

Circuit to prevent relays 7 and 8 'from=c0ntacting"until dies are closed When microswitchspositionI76 is closed, this-energizes relay 78fand,'.hence, closes points 79, 191 and 192,,as indicated supra. When point 192 closes, .we have asafety circuit from. point 192 which is. connected. on oneside to lead 36 to 24volt pilot-circuit. From relay 78nat thecother sideof point 79, We provide. a lead 8llwhich connects to relay coils .7. and.8 in series. Referring, to coil 8, we have a lead 84 connectedto point .201 of relay. 127, throughsalidpoint-ZOI, leads and 48 to th'eotherisde of the24 volt circuit at point 490i relay-29,

This safety circuit, just described, also controls. relay 7. Thus, from 'lead 80. (for relay 8) we alsohave a lead '81ito relay Tandlfrom relay 7 by lead 82-we connect to point184 of relay through point to lead 18.4, hence to point 49 of relay 291 Thus, it Will'be seen thatlb'othrelays 7 and 8 arein: terconnected in the, systemso that these relays. cannot be closed when the dies .are opening, since .relay 78,.would be open, and,hence, point 79wouldbe openiandlbreak the-circuits for both relays 7 and 8.. Thus, if tubes l'or 2"fi'red, due to a fault, then relays7 and 8 Would'not operateto inject metal intothe. dies.

Microswitch must be in correctposition 'We haveafurther circuit to. correct a condition, when in operationrnicroswitch 40 'becomesjjammedrin position requiring an'injection of metalinto the die. This addi'-' tional circuit acts as a safety circuit-to prevent such an improper injection of metal in case operator presses close button. When operator pressesclose buttonpoint 30of the special switching remote control connections indi'cated'at 13 to start'autornatic cycle voltage control, through point 43, safety button-point 30, lcad4'1, through safety point 40"of the microswitch, lead 38' to coil137, which completes the closing circuit for coil '37., this closes the machine. However, itwillbe seenthat if switch 40' is in metal'injecting position, the operator will not'he able to close the machine, since point 40 would be open if the microswitch is not in its normal position for the start of the cycle.

Safety circuit to prevent machine'operation by accidental closing of microswitch We also have a. normally closed point 40 of the microswitch connected in such a manner as to prevent operator from closing the machine if the microswitch is jammed. If point 40 of microswitch is closed accidentally, unless at correct normal position, relay- 37 .has not been energized, leaving point 57 normally open. Relay 15,8 and associated points 159 'and 160. are actuallythe controllingpoints for the two-stage metal injection through coils 7 and 8. Thus, if microswitch is accidentally closed, causing. relay 78 to close, starting shot cycle, relay coil 158 will not be energized even if point 192 of relay 78 has closed, because the other side of coil 158 has its circuit broken, by normally; open point 57 whichwill not be closed unless machine. is; in normally operating cycle. The manually controlled automatic. station and the microswitch control circuits are therefore dependent upon each other as indicated.

Emergency switch for stopping automatic action and causing machine t0open andlmechanism to be reset in the automatic operation of one complete cycle of themachine, the relay 37 acts as an electric self tying in means for effecting the. supply of current to the various circuits heretofore described. As will be seen from Figure I- and the foregoing description, this current supply is a 24 volt circuit which has several leads includingflead 440m one side and 36 onthe other. We also provide, however, an emergency switch in the form of a. momentary contact 43 which is normally closed, but which may be opened to break this locking in circuit. Referring to the drawings, this is accomplished as follows:

The 24 voltcircuit referred to flows from lead 44 through the normally closed, momentary breaking safety button 43, through lead 62, point 202, lead160, to relay 37; This relay 3.7 is energized when the machine is operating,'in. which case: point 5.7 of this relay 37' will be closed. Thus, current from leads through point 57, lead 56, to point 54 of relay 55, through this point, through leads 53 and 38, to the coil of 37, back by lead 36, which is the other side of the 24-volt supply. Since the locking-in 24 volt circuit for relay 37 is supplied between the leads 36 and 44, and this emergency safety button 43 is interposed between these two leads, it will be seen that when the operator opens the switch 43, the locking relay 37 is released and the shot cycle resets and the dies of the machine open.

Pilot light for heat control instrument We also have a heat control pilot light 203 in a circuit to the 24 volt transformer 26 connected on one side through leads 51, 204, 108, 205, light 203. From the other side of light 203, we have a lead 206 to leads 207, 105 and lead 31 to the other side of transformer 26. Thus, when the heat control on and off switch 23 is closed (which is a toggle switch) it energizes relay 208 through leads 209 and 210 applying 440 volts to transformer 25 (primary) to supply 110 (secondary) for the heat control motor and gas valve (not shown). Also, this energizes transformer 26 from the 220 secondary of transformer 25, which supplies 24 volts to the pilot light 203 through the circuit just described supra. When switch 23 is closed, it applies 24 volts to the pilot lamp 203 showing the operator that the heat control and gas valve section of the cabinet is on. Relay 208 has a transformer 211, the control circuit of which is 24 volts supplied by said transformer 26. This avoids the necessity of supplying 440 volts at any time to the control section of the cabinet.

Pilot lamp for indicating machine ready for automatic action We also provide a lamp 198 connected by lead 199 to lead 47, hence to point 49 of relay 29. On the other side, lamp 198 is connected by lead 34 to point 32 of relay 29. Operator closes switch 104, thereby energizing relay 28, throwing the circuits into automatic position. This energizes bias transformer 88 and connected circuit which, at the end of its time delay (allowing tubes 1, 2, 3 and 4 to warm up), closes point 107 of relay 106, energizing relay 29. This applies the 24 volt control circuit across pilot lamp 198 and also supplies 24 volts to the automatic control section and, hence, shows the operator that the tubes 1, 2, 3 and 4 have been heated sufficiently for operator to close button 30 to start machine in automatic operation, but there is no control voltage on the automatic section until this abovementioned time delay has expired.

Manual control circuit We have a manual automatic switch 104 operable when relay 28 is not energized. The control by switch 104 is dependent on switch 212. Thus, if manual switch 212 is closed, 24 volt control voltage from transformer 27 will flow through lead 31, lead point 213 of relay 29, lead 214 to the manual open and close switch 212, lead 215, point 216 (closed) through the lead 68 to the coil of relay 6 for the die operating mechanism. The return circuit is through lead 69, point 217 (closed), lead 218, to point 219 (relay 29), lead 50, lead 51, to other side of control transformer 26. Thus, when the n1echanism is in manual position, determined by the position of switch 104, and switch 212 is closed, 24 volts is applied across the coil of relay 6, operating coil 6 and, hence, pilot valve 9 to close and open the dies of machine, but the rest of machine, including metal injection, will not operate.

44- 60 passes Re'sum of circuits-Figure I From the foregoing, it will be seen that we provide the following main circuits and controls:

(1) POWER INPUT CIRCUIT (2) TRANSFORMER AND VARIOUS TRANSFORMER CIRCUITS We provide a preliminary transformer 220 and connecting circuits therefor; the main transformer 25 for providing circuits for 220 volt and 110 volt; 24

volt control circuit transformer 26 and the bias circuit transformer 88 all with interrelated circuits, as herein appears.

(3) MACHINE OPERATING CIRCUITS (4) CONTROL CIRCUITS We provide several interrelated and interconnected control circuits to properly effect the application of the foregoing machine operating circuits just referred to. These control circuits are supplied with current at 24 volts and primarily are for operating the coils 6, 7 and 8 to, in turn, effect an operation of the die closing mechanism and the two-stage metal injection referred to. These control circuits are basically controlled by the thyratron tubes 1 and 2, tube 3 being for temporarily resetting bias on tubes 1 and 2 and tube 4 for effecting opening of the dies and resetting entire bias to initial position. We also provide a control for effecting an operation of the circuit to the oil pressure motor 12 through contactor 23 through push button stage 87. Each of these circuits includes the various relays as hereinbefore set forth, a complete operation following this list of circuits. The supply of control voltage to coil 6 is primarily through relay 37 when the automatic system has been put into operation through the close button manually operated switch 30. For energizing coil 10 by means of control coil 7, we provide relay connected in the plate circuit of tube 1 for effecting this result. For operating coil 11 through control coil 8,

relay 127 in the plate circuit of tube 2 produces this action.

that we pro- (5) SAFETY CIRCUITS From the foregoing description, it is also clear that we provide pilot lamp indicators to advise the operator of the machine the various conditions as referred to in describing said pilot lamps.

Operation-One complete cycle As heretofore indicated, the machine is started by the operator closing the quick return close button 30, one side of which is connected to the power inlet and through leads and switches to locking in relay 37, hence, relay 28 and correlated circuits and controls from the relay 29 which is connected with the 24 volt transformer 27 to supply current thereto, through the various circuits, heretofore described and clearly shown in Figure I, which causes the coil 6 to close the power circuit through the operating coil 9. This action will close the dies of the machine as indicated in Figure III.

As the dies are closed, the microswitch is operated by a part of the die closing mechanism to thereby throw the microswitch to closed 76 position and effect an energization of relay 78. The machine is held by a mechanical action of a toggle mechanism. Relay 78 closes switch point 192 and relay 158 is energized, opening point 159 which is in the bias circuit for tube 1, as described supra. Opening the tube 1 bias permits tube 1 to fire at the end of its time delay through its plate circuit, thereby energizing relay 120, closing switch point 184, as stated supra. This, through the various circuits, above described, energizes relay 7 which, in turn, supplies power to the pilot valve for the main air cylinder 10, permitting a delayed shot of metal at reduced pressure to be injected into the die as the first part of the two-stage metal injection. Specifically, closing of switch point 184 by a oar v .thedischargepfiWbe lconnects lead. 1841.10 point 49 .of relay 29,. point. 49.bjeing. normally closed, hence, to. lead V 51 of the24 volt transformer 26 and back to switchpoint 184 of relay 120 which connects the current to lead 82 and as clearly-shown in the drawing, to relay 7. The

other side of this relay .circuitincludes leads 81,. 80, to point 79 of .81 .toswitch 32, lead 31 relay 78 (now .closedthrough'79, lead 80,

to transformer 26). The firing of tube 1 energizes coil. 7 and hence solenoid Temporary auxiliary circuit forbiasing tubes 2 and 3 Firing of tube 2 -It' willbe noted from the wiringdiagram of'Figure I,

-- that we also provide, in addition to the main biasing cir .cuit above described, an auxiliary bias circuit for tubes 12 and 3. To this end, it will be noted that we provide a 'lead' 166 from main bias supply lead154, lead 166 connected through normally closedpoint 167 of relay.120 and lead 221 to the bias circuit 171, etc., for tube 2.

' This auxiliary circuit for tube 3 we provide in an additional lead 164 extending from point164 of relay 133, :hence, by lead 179 to lead '175 which connects tothe bias-circuit of tube'3. This auxiliary biasing circuit for tubes 2 and 3 is on temporarily simultaneously with the main bias supply described above.

Firing Tube 2 It will be noted as indicated. above, when relay 158 has been energized, the main supply bias at switch points 160 and161 have also been broken .at the same time when -the-bias supply was brokento tube 1. However, the

auxiliary bias supply circuits for tubes '2- and 3 still preventsttubes 2 and 3 from firing.

By the firing of tube 1, just described, this auxiliary bias for tube 2 is also. openedbecause switch point 167 ,which;-is in-the'bias circuit'for tube .2, has now'been opened by relay 120. Removing tube 2 bias causes the discharge of its circuit at the end ofits time delay and energizes relay 127. Thus, when point 201 is closed, {GUIIGIUZ is suppliedfrom the-transformer 26 to coil 8 circuits 2and switches, since we have provided a lead from .the lead 184, numbered 105, :to switch point 201 (lead 184 being connected to transformer 26 as just described), .-.and.from switch 201, lead 84 tocoil 8. On the other -side of coil 8, we have a lead which joins lead 80 just described. Hence, the connections are established back .-to the transformer 26, as just described, in connection -.with tube 1. As will be understood from the foregoing, the energization of coil 8, in turn, connects the 440 volt power line to the coil 11 of the air pilot valve which causes the main-injection of metal at high pressure into the closed-die.

It willbe noted that by a proper :adjustment of the potentiometers 222, particularly for tube 2, we have;provided controlling means or an'interconnected mechanism so that the time at which the low pressure injection of .metal is changed to a high pressure injection may be varied throughout the entire range of movement of; the .air plunger which actuates the metal injecting;- piston. l lowever, .since the time delayin the'firing of tube 2 .after both bias circuits have been removeddepends on setting of the variable potentiometer 222 fortube 2, by

adjustrnent thereof to its low position, tube 2 may fire' substantially immediately after tube 1 fires so that in the overall operation of the network sequentialfiringsystem .disclosed, tubes 1 and 2 in such casefire without any appreciable difference in timebut act .as-one tube.

Holding the pressure of the metal in the dies-Known asset time 222 of tube '3 prevents .its discharging until [the metal hasset in the die as describedsupra.

After set time, firing'of tube 3 Next the cycle :of operations, We provide :means.

. -1h1'0l1gl11'fl18 firing of tube3 to reset the bias circuits or tubes Land. 2. This is done by establishinga-temporary additional biasing circuit hereinafter described. The resetting of the bias of tubes 1' and 2 isdone primarily'by first: removing the above-described auxiliary bias-from tube 3 by opening the switch point 178 of relay-127 which, as stated supra, occurs when tube 2 fires. -Removing the bias from tube 3 therefore causes a discharge after the time delay shown, as will be understood, through its plate circuit. Firing of tube 3 energizes. relay 133 which is in the plate circuit of tube 3, as shown, so that energization thereof closesswitch points 162 and 163, whichare in an additional temporary bias circuit which,

uas-shown in: the drawings, includes mainsupply line 154 which is connected. through the now closed switch points 162 and 163,.point 162 connected to the bias of tube 1 through 163 and 168 while the temporary additionalbias for tube 2 is connected through point 163, lead 171, lead 171 connecting to the bias of tube 2. By closing these switch points 162 and 163, through these additional circuits, just described, tubes 1 and 2 are rebiased. It is understood that when the proper bias is-applied to tubesl and 2, discharge thereof through the plate circuit ceases.

. another switch :point 164 for relay 133 so that when relay 133 is energized, as just stated, this switch. point 164 opens with the result that reestablishing bias through the additional circuits just described to tubes 1 and 2 will not also reestablish, through the auxiliarycircuits, bias to tube 3.

From the foregoing, it will 'be understood that when bias is reestablished to tubes 1 and 2, these tubes cease firing :and coils 7 and 8 are deenergized, permitting solenoid operated pilot valves 10 and 11 to be returned to normal position. After tube 3 has fired, the apparatus is in the position in which the pressure has been removed from the metal in the dies and a periodof .time,.called the cooling time, is allowed for the metal to cool,.which. is the time preceding the firing of tube-4 in our electrical circuits, the cooling time being controlled by potentiometer222 of tube 4.

Firing of tube 4 opens the dies.--Machine and circuits thereby reset to initial position Firing of tube 4 accomplishes the reopening'of the dies. Referring back to tube 3, it will be noted that when it fires, it has opened switch point 165 on relay 133 which, in turn, removes the bias from tube 4 after its time delay through its potentiometer circuit, tube 4. When the bias on tube 4 is removed, then the tube discharges, energizing coil 55, opening point 54 on relay 55, thereby breaking the holding circuit for relay .37 which drops outrelay 37. Since, as described above, it isthe energization of locking in relay 37 which closes the dies, the opening of the circuit thereof permits .the apparatus to complete the cycle and return to original position.

Automatic rebiasing of each of the tubes after mechanically completing one cycle of machine operation and 161 so that now the main bias is resupplied to both tubes 3 and 4 as well as to tubes 1 and'2. This is due to -the fact that the bias supply line 154, as indicated supra, is connected with points 159, and 161 controlled-by relay 158 andunder normal inoperative position of the .machine the closing of these points closes the bias circuit through lead 168 to tube 1,'the lead 171 for the bias circuit to tube 2, the lead 175 .for the bias circuit to tube 3. It will be'also noted that the main bias supply lead line 154 is connected with relay point of relay .133 and since this point is now closed, lead. 180. supplies the bias to tube 4. Point 165 is closed because of the fact that tube 3 has now' been rebiased and'ithereiore relay 133.has beendeenergized, andspring meanscloses the contact 165. Rebiasing tube 3 in this manner thereupon permits its relay coil'133 to operate, breaking points 163 and162, thereby'disconnecting the additional bias circuit which was temporarily established for. tubes -1:1and:2. The entire electrical apparatus is now-*ininitial 13 position. The machine then will not recycle until the operator restarts the cycle by pressing manual close button 30, as described supra.

In referring to the bias supply circuits for the several tubes, we have referred herein to the main bias, an auxiliary bias and an additional bias. However, it is to be understood that the various circuits-some leads of which are common to the dilferent circuits-for supplying bias at the proper time to the different tubes, according to the drawings and description, may be properly termed additional or supplemental with respect one to another of the bias circuits.

Interconnection control for supply of bias and plate circuits of tubes for warm up time and to open plate circuits upon failure of bias supply It will be noted that we have an important interconnection in the circuit arrangements so that before the machine can be operated, there is a warm up time for the several thyratron tubes and also an interconnection so that if the bias should fail, due to abnormal conditions, such failure opens the main plate circuits of the several tubes so that they would not discharge, as otherwise this would cause an improper operation of the die casting machine. Circuit 144 is for the heaters of the thyratron tubes.

The transformer 88 provides a volt circuit 145 for the filament of the rectifier tube 89. Also the bias circuit for the several thyratron tubes 1, 2, 3 and 4 is supplied from transformer 88 (changed to D. C. by rectifier tube 89), the bias circuit including center tap winding 148, lead 223, voltage reducing resistor 157, branch circuit, lead 149, filter condenser 150, which is grounded as shown. The outside of said winding 148 is connected to the plates of rectifier tube 89, the filaments thereof also grounded as shown. (The cathode circuits for each of the thyratron tubes are likewise grounded.) Resistor 157 also has a connection through main lead 156 to the coil 106 which, being in the bias circuit, as stated above in the description, and shown in the drawings, is also arranged to act as a combined choke and relay, the point 107 being of the type which is slow making and quick breaking. Connected to the coil 106 by lead 152, which connects by lead 153 to the main bias supply line 154 for the main thyratron tubes, we also provide a further regulating means in the regulating tube 151 which is grounded as shown. Moreover, across the tube 151, a resistor 155 is further employed to control the circuits, resistor 155 being grounded as shown.

The switch 107 of coil 106 is, as shown, in the supply circuit for the plate voltage of the several thyratron tubes, so that upon energizing relay 106, the slow closing of the plate circuit through switch point 107 gives the tubes a chance to warm up in their internal circuits before the plate voltage supply is connected to said tubes. Moreover, as stated supra, if there is any failure in any of the bias supply circuits for the tubes, since the same passes through relay coil 106, and this must be energized to close switch 107 in the plate circuits of the tubes, failure of the bias circuit opens the relay point 107 and, hence, disconnects the plate supply circuits to tubes 1, 2, 3 and 4.

Manual control for operating opening and closing 01 dies and circuits In order to permit the operator to open and close the dies at will without the rest of the machine operating, as may be necessary, we provide an independent circuit manually controlled, which operates merely the coil 6 for operating the die closing mechanism.

Thus, we provide a manually controlled switch 212, which is a circuit extending from the transformer 26 to energize coil 6 independently of the automatic controls described above, said circuit being established to the power input or disconnected therefrom according to the position of the manual-automatic changeover switch 104. For one side of manual switch 212, we provide a lead 215 and a lead 214, which extends to points 213 on relay 29 closed with the manual-automatic changeover switch 104 in the manual position. From switch point 213 of relay 29, lead 31 connects to the 24 volt circuit from the transformer 26. Then, by lead 51, lead 50, switch point 219, lead 218, switch point 217 of relay 28, normally closed under these conditions to lead 69 to coil 6. From the other side of coil 6, lead 68 connects to switch point 14 216 and from lead 215 to the other side of main manual switch 213, just referred to.

In order to accomplish the foregoing, as indicated, we provide the relay 28 to isolate the rest of the machine so that this manual control may be operated. In order to accomplish this isolation, we provide the relay 28, whose energization is controlled from the manual-automatic switch 104 so arranged that when this switch 104 is in the manual position, it deenergizes relay 28, and when in the automatic position, it energizes this relay. Thus, we provide from relay 28, lead 103 to 104, to switch 104, lead 105 to lead 31, transformer 26, lead 51, lead 102 to relay 28. It will thus be seen, if the manual-automatic switch 104 is opened, 28 is deenergized and a control of the dies through the manual switch 212 may be accomplished. However, if the operator closes switch 104, the coil 28 is energized, and this will open the circuit from switch 212 to relay 6. Hence, even if the operator might manipulate the hand switch, no energy would be supplied to coil 6.

It is apparent that, within the scope of the invention, modifications and different arrangements may be made other than is herein disclosed, and the present disclosure is illustrative merely, the invention comprehending all variations thereof.

What we claim is:

1. In a control network for a plurality of loads adapted to be energized from a power supply source; said network including electrical circuit establishing means interposed between said source and said loads including electrical connections therefor; a quick return manual control switch in said connections for initially energizing said control network; a tying-in relay adapted to connect said network with said source; a shunt circuit for by-passing said manual switch and located in said circuit connections arranged to connect said source of power and the first of said loads through said tying-in relay; a timer mechanism; controlling relay means in said network; and circuits in said network from said source of power to the second and subsequently operated loads established by said timer mechanism under the control of said relay means; and a machine part operated switch in said network for controlling the energization of said relay means, said circuits including lead connections in said network whereby energization of said loads subsequent to said first-mentioned load is dependent upon the interaction of said tying in relay, said controlling relay means and said timing mechanism.

2. In a control network for a plurality of loads adapted to be energized from a power supply source; said network including electrical circuit establishing means interposed between said source and said loads including electrical connections therefor; a relay for establishing voltage to said circuits a quick return control switch in said connections for initially energizing said control network; a tying-in relay adapted to connect said network with said source; a shunt circuit for by-passing said switch and located in said circuit connections arranged to connect said source of power and the first of said loads through said tying-in relay; a timer mechanism; controlling relay means; circuits in said network from said source of power to the second and subsequently operated loads established by said timer mechanism under the control of said relay means; said timer including means for controlling said network to effect deenergization of said second and subsequent loads and thereafter deenergizing the first load; an electrical interconnected circuit between said supply and said timer mechanism and said first-mentioned relay; a switch in said last-mentioned circuit in series with said relay; and means controlled by said timer mechanism for closing said switch whereby energization of said supply line relay is under the control of said timer mechanism.

3. In a control network for a plurality of loads adapted to be energized from a power supply source; said network including electrical circuit establishing means interposed between said source and said loads including electrical connections therefor; a quick return manual control switch in said connections for initially energizing said control network; a tying-in relay adapted to connect said network with said source; a shunt circuit for by-passing said switch and located in said circuit connections arranged to connect said source of power and the first of said loads through said tying-in relay; a timer mechanism; controlling relay means; circuits in said network from said source of power to the second and subsequently operated loads. established by said ,ltimergmechanisrn under the control of said relay means; a machine operated switch zfor controlling voltage supply to said relay means; said rtimervincluding means for controlling said network to .eifect deenergization of said second and subsequent loads and thereafter deenergizing the first load including means 4 for breaking said shunt circuit and deenergizing said tying-in, relay.

4. In a control network for a plurality of loads adapted to be energized from a power supply source; said network including electrical circuit establishing means interposed between said source and said loads including electrical connections therefor; a quick return manual control switch in. said connections for initially energizing said control network; a tying-in relay adapted to connect said network 'with said source; a shunt circuit for by-passing said switch i and located in'said circuit connections arranged to connect saidsource of power'and the first of said loads through said tying-in -relay;. a timer mechanism; a controlling relay; circuits in said network from said source of power to the second and subsequently operated loads established a by said timer mechanism under the control of said relay; ra-machine operated switch for controlling energization of asaidrelay means;,a circuit breaking-relay operated switch in said connection to said first load, said switch being normally closed; and means to actuate said relay to open said-normally; closed switch, said last-mentioned relay controlled by said timer mechanism.

5. In a control circuit network fora plurality of loads adapted to be connected to a current supply source; a quick return manual control switch in said network; a :machine part-operated switch; circuits in said network initially connected to pass, current through both said switches in series; a tying-in relay in said network; a shunt circuit by-passing both said switches established by -said tying-in relay adapted to energize the first of said loads; a sequentially operating timer mechanism; relay "means for controlling the operation of said timer; circuits from said source of powerto the second and subsequently operated loads adapted to-be-established by said timer -mechanism under the controlof said relay means; a voltage establishing relay in the network for supplying -voltage-thereto from said source; and means to operate :said last-mentioned relay whereby current is supplied 'rinitially through :said network to energize the first of said loads,-said network subsequently energizing the other "loads insequence, controlled'by said machine operated switch when in its cycling operating position, said timer mechanism and said circuits arranged to effect one complete cycle" ofroperations and thereafterdeenergize said ifirst load andxeffect return of said machine operated switch to its initial position.

6. In a control network for a plurality of loads adapted to-beconnected with a current supply source; said network including circuits having a quick return manual control switch and a two-posrt-ionmachine part operated switch havingv an initial and asecond operative position; said -circuits rmitially passing through said first-mentioned switch and the first position of said other switch in series;

2 a' tying-in reiay for; connecting said network with said source; a shunt circuit by-passing said first-mentioned switch and the first position of sald other switch; a timer "mechanism; controlling relay means; and circuits in said network from said source of power to the second and the subsequently operated loads established by said timer mechanism under the control of said relay means, said last-mentioned circuits including said two-position switch when'in its second operative position.

7. in a control network for a plurality of loads adapted to be connected with a current supply source; said network including circuits having a quick return manual control switch and a two-position machine part operated switch having an initial and a second operative position; said circuits initially passing through said first-mentioned switch and the first position of said other switch in series; a tying-' in relay for connecting said network with said source; a

shunt circuit ivy-passing saidfirst-mentioned switch and the first position of said other switch; a sequentially operating timer mechanism: controlling relay means; circuits y in said network from said source of power to the second and thersubsequently operatedloads adapted to be estabished bysaid'tirnermechanism under the control of said zrelay means,,said last-mentioned circuits including said 7 -two pos1t-ion switchv when in its. second operative position;

, and return circuit connections for the first load extending ,.avoltage supplying relay in said network connected to said source of power.

8. In a control network fora plurality of loads adapted -to be energized from a power supply source; electrical between said transformer and said load including a supply lead to a first relay; leads therefrom to said tying-in relay, lead connections therefrom to said first load; and a return circuit therefrom to said transformer; a quick return manual control switch in said establishing means for initially effecting energization of said control network; a temporary circuit between said switch and said first load network circuit including leads from said first load supply line through said tying-in relay to said manual switch and therefrom back tothe return line of said first load circuit; a shunt circuit for by-passing said manual switch and connecting said circuit from said transformer to said first load, said shunt passing through said tying-in relay and includingleads from said tying-in relay to the return side'of said manual switch and from said side ofsaid switch through said starting circuit leads to said return line of said first load circuit; a timer mechanism; timer controlling relay means; circuits insaid network from said source of power to the second and subsequently operated loads'established by said timer mechanism under the control of said relay means; the circuit to the second load including a lead from the first load supply line adjacent said tying-in relay to said timer relay means, load connections between said relay and said second load;

a return line having a lead to said timer; a lead from said timer to the return lead of said first load energizing circuit; the circuit to the third load comprising a lead from the supply line of said second load, said lead connected to said third load and a return line including a lead from said third load to said timer and leads therefrom to the return line of said first load circuit; a circuit breaking switch in said shunt connection to said source; a relay for operating said switch, said last-mentioned relay controlled by said timer mechanism to open said switch after one cycle of operation of said loads and arranged to thereafter reset said shunt circuit switch at the end of said cycle.

9. In a control network for a plurality of loads adapted to be energized from a power supply source; electrical circuit establishing and controlling means interposed bctween said source for controlling the operation of and energizing said loads including electrical connections therefor; said means comprising an input transformer-energized from said source; a tying-in relay adapted to connect said network with said transformer; a supply and return circuit connections for the first load extending between said transformer and said load ineluding a supply lead to a first relay; lead connections therefromto said tying-in relay, leads therefrom to said first load; and a return circuit therefrom to said transformer; a quick return manual control switch in said and from said side of said switch through said starting circuit-leads to said return line of said first load circuit; a n automat1cally operating multiple releasing and resettlflglln'lfil' mechanism; timer energizing and controlling 1 relay means; circuits-in said network from said source of power to the second and subsequently operated loads controlled by one of the units of said timer mechanism under the control of said relay means; intercontrolling circuits between said timer and said first relay, the circuit to ,the second load including a lead from the first load supply line adjacent, said tying-in relay to said timer re- .lay means, load connections between said relay and said second load; a return line having a lead to said timer; a

lead from said timer to the return lead of said first load energizing circuit; means to energize said first load circult upon release of the first unit of said timer mechanism; the circuit to the third load comprising a lead from the supply line of said second load, said lead connected to said third load and a return line including a lead from said third load to said timer and leads therefrom to the return line of said first load circuit; means to energize said third load circuit upon release of the second of said timer units; means to deenergize said first and second load circuits upon resetting of said first and second timer units of said timer mechanism by release of another unit of said timer; a circuit breaking switch in said shunt connection to said source; a relay for operating said switch, and means to actuate said relay to open said switch after one cycle of operation of said loads, said last-mentioned relay controlled by the release of the last operating unit of said timer mechanism; and means to reset said shunt circuit switch at the end of said cycle controlled by the resetting of the last unit, said relay timer controlling means resetting the other unit released upon one cycle of operation.

10. In a control network for a plurality of loads adapted to be energized from a power supply source; electrical circuit establishing and controlling means interposed be tween said source for controlling the operation of and energizing said loads including electrical connections therefor; said means comprising an input transformer energized from said source; a tying-in relay adapted to connect said network with said transformer; a supply and return circuit connections for the first load extending between said transformer and said load including a supply lead to a first relay; lead connections therefrom to said tying-in relay, leads therefrom to said first load; and a return circuit therefrom to said transformer; a quick return manual control switch in said establishing means for initially effective energization of said control network; a temporary circuit between said switch and said first load network circuit including leads from said first load supply line through said tying-in relay to said manual switch, a two position machine part operated switch in said circuit, and a return lead from said manual switch back to the return line of said first load circuit; a shunt circuit for by-passing said manual switch and connecting said circuit from said transformer to said first load, said shunt passing through said tying-in relay and including leads from said tying-in relay to the return side of said manual switch and from said side of said switch through said starting circuit leads to said return line of said first load circuit; a timer mechanism; timer controlling relay means; current supply and return leads from said source to said relay means, the second position of said two-position switch located in said circuit when closed, closing said last-mentioned circuit; circuits in said network from said source of power to the second and subsequently operated loads established by said timer mechanism under the control of said relay means; the circuit to the second load including a lead from the first load supply line adjacent said tying-in relay to said timer relay means, load connections between said relay and said second load; a re turn line having a lead to said timer; a lead from said timer to the return lead of said first load energizing circuit; the circuit to the third load comprising a lead from the supply line of said second load, said lead connected to said third load and a return line including a lead from said third load to said timer and leads therefrom to the return line of said first load circuit; a circuit breaking switch in said shunt connection to said source; a relay for operating said switch, and means to actuate said relay to open said switch after one cycle of operation of said loads, said last-mentioned relay controlled by said timer mechanism and arranged to deenergize said first load, causing said two-position switch to return to its first position breaking the circuit to said timer relay controlled by said second position of said two-position switch.

11. In a plural load controlling network adapted to energize certain loads in a sequence from a source of electrical energy, said network having a timer mechanism, a timer relay controlling means and circuits including a tying-in relay between said source and each of said loads, a quick return starting switch in said network; a two-position machine operated switch therein; and single cycling starting and establishing circuits for said network including leads between said source, the first 18 load and said tying-in relay to the first position of said two-position switch; a lead therefrom to said quick return switch; leads therefrom to the return circuit between said tying-in relay and said source whereby closing said quick return temporarily energizes said first load; a shunt circuit from said source to first load circuit, said shunt established by said tying-in relay for maintaining energization of said tying-in relay upon opening of both said quick return switch and the first position of said twoposition switch, said shunt circuit maintaining the connection of the first load and the source for one cycle of operations; means to control energization of the subsequently operated loads by the second position of said twoposition switch including leads from said timer controlling relay means to said second switch position and leads therefrom to the network leads from said power source through said subsequent loads, the circuits arranged so that upon one cycle of operation, deenergization of the first load by said timer mechanism operates to open the circuit to said tying-in relay, efiect restoration of said two-position switch to its first position, and deenergizes said shunt circuit, restablishing the initial circuits of said network.

12. In a plural load controlling network adapted to energize certain loads in a sequence from a source of electrical energ said network having circuit leads and controls between the source and said loads including a timer mechanism; a timer relay controlling means; an intcrcontrol relay between said timer mechanism and said circuit leads whereby energization of said leads from said supply to said network is dependent upon said timer mechanism; a tying-in relay between said source and said loads, a quick return starting switch in said network; a two-position machine operated switch therein; and single cycling starting and establishing circuits for said network, leads from said source including the first load and said tying-in relay and the first position of said two-position switch; a lead therefrom to said quick return switch; leads therefrom to the return circuit between said tying-in relay and said source whereby closing said quick return switch temporarily energizes said first load; a shunt circuit from said source to first load circuit, said shunt established by said tying-in relay for maintaining energization of said tying-in relay upon opening of both said quick return switch and the first position of said two-position switch, said shunt circuit maintaining the connection of the first load and the source; means to control energization of the subsequently operated loads by the second position of said two-position switch including leads from said timer controlling relay means to said second switch position and leads therefrom to the network leads from said power source through said subsequent loads, the circuits arranged so that upon one cycle of operation, deenergization of the first load by said timer mechanism operates to open the circuit to said tying-in relay, effect restoration of said two-position switch to its first position, and deenergizes said shunt circuit, reestablishing the initial circuits of said network.

13. In a control network for a plurality of loads adapted to be energized from a power supply source; said network including electrical circuit establishing means interposed between said source and said loads including electrical connections therefor; a quick return manual control switch in said connections for initially energizing said control network; a tying in relay adapted to connect said network with said source; a shunt circuit for bypassing said manual switch and located in said circuit connections arranged to connect said source of power and the first of said loads through said tying in relay; a timer mechanism; controlling relay means; circuits in said network from said source of power to the second and subse quently operated loads established by said timer mechanism under the control of said relay means in a predetermined sequence; a machine operated switch for energizing said relay; and electrically operated circuits and controls actuated by said timer mechanism to deenergize said second and. subsequently actuated loads simultaneously, said timer mechanism arranged to deenergize said first-mentioned load after said simultaneous deenergization of said second and subsequent loads and restore said network to initial position after each cycle of operation effected by said manual control switch.

14. In a control network for a plurality of loads adapted to be energized from a power supply source; said network including electrical circuit establishing means interposed between said source and said loads including electrical connections therefor; a quick return manual control switch in said connections for initially energizing said control network; a tying-in relay adapted to connect said network with said source; a shunt circuit for bypassing said manual switch and located in said circuit connections arranged to connect said source of power and the first of said loads through said tying-in relay; a second normally closed, manually operable emergency switch in said shunt circuit; a timer mechanism; controlling relay means in said network; circuits in said network from said source of power to the second and subsequently operated loads established by said timer mechanism under the control of said relay means; a machine part operated switch in said network for controlling the energization of said relay means, said circuits including lead connections in said network whereby energization of said loads subsequent to said first-mentioned load is dependent upon the interaction of said tying-in relay, said controlling relay means and said timing mechanism, said electrical circuit establishing means arranged whereby opening of said emergency switch, opens the circuit of said power supply source to each of said loads.

15. In an electrical system adapted to be manually or automatically controlled, said system including a plurality of loads, a source of power and circuits and controlling means adapted to connect and disconnect said loads and said source including an automatically operating network to energize and deenergize all of said loads in a predetermined sequence for one cycle of operation; a manually controlled network for energizing and deenergizing one of said loads only; switching means to connect and disconnect said automatic network and said source and to selectively connect and disconnect said manual network to said source; and relay means in the circuits between said source and both said networks including two interrelated relays, each having a plurality of switch points, said manual and automatic networks having common leads to the first of said loads, said selective switching means interconnected with said relays whereby energization of said first load by both networks is controlled by the position of said selective switching means and certain of said switch points on both said relays.

16. In a manual-automatic load controlling and actuating electrical system, adapted to be connected with a supply source; an automatically operating network for energizing a plurality of loads from said source in a predetermined sequence; timer mechanism therein; said automatic network including certain leads for the first operated of said loads and certain leads common to and certain leads separate from said first load leads for operating said additional loads; a manual controlled network for the energization of one only of said loads; a pair of interconnected relays between said source and both of said networks, each relay having an energizing coil and a plurality of switch points connected in said networks; the portion of said automatic network for said first operated load and said manual network for said first load adapted to be connected for energization through switch points of both said relays and the other portions of said.

automatic network connected for energization through one only of said relays; manually operable switching means and connections with both said networks arranged for manual and automatic positions to selectively connect said manual network and disconnect said automatic network from said source, or connect said automatic network and disconnect said manual network therefrom; and an additional manually operable cycle controlling switch in said automatic network whereby said automatic network is under the control of said last-mentioned switch when said change-over selective switching means is in automatic network energizing position.

17. In a manual-automatic load controlling and actuating electrical system, transformer means adapted to be connected with a supply source; an automatically operating network for energizing a plurality of loads in a predetermined sequence including a timer mechanism therein; a manual controlled network for the energization of one only of said loads; a pair of interconnected relays between said transformer and both of said networks for supplying electrical energy thereto; each relay having an energizing coil and a plurality of switch points connected in said networks, certain of said points being closed when said coils are energized and other switch points closed upon deenergization of said coils; each of said networks having common leads between one of said relays and one of said loads and common leads between said transformer and said other relay; the coil of each relay connected to be energized from said transformer; and manually operable switching means and connections with both said networks arranged for manual and automatic positions to selectively energize said automatic network from said transformer or energize said automatic network therefrom, the coil transformer circuit for one of said relays including a switch and means to open and close said switch controlled bysaid timing means in said automatic network and the transformer coil energizing circuit for the other relay including said changeover switching means.

18. In a manual-automatic load controlling and actuating electrical system, said system adapted to be connected with an electrical current supply source, a plurality of loads; an automatic network for energizing a plurality of said loads in a predetermined sequence; a timer mechanism in said automatic network; circuits arranged for connection with said automatic network for the manual control and energization of one only of said leads; a pair of interconnected relays each having a plurality of switch points arranged for connecting said electrical source and said networks; the plurality of switch points for each relay including two pairs of unitary acting double switching points and a single connection for each switching unit of each pair; a common supply lead for both automatic and manually controlled network operation to the first load from one of the single connections of one relay; a common return lead for said automatic and manual connections from said load to the single connection for the other double switch of said last-mentioned relay; common supply and return leads for both said automatic and manual circuits from the current source to the single connections for each of the two sets of double switching points for the other relay; switching means to shift said electrical system to disconnect said automatic network connections and connect said manual circuit connections to energize the first only of said loads, said switching means arranged to deenergize the coils of both of said relays to move said sets of double switch points of said relays to connect said common supply and return leads to said first load to energize said first load for manual operation.

References Cited in the file of this patent UNITED STATES PATENTS 2,555,994 Pennell June 5, ll 

